Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* xfrm4_tunnel.c: Generic IP tunnel transformer. |
| 2 | * |
| 3 | * Copyright (C) 2003 David S. Miller (davem@redhat.com) |
| 4 | */ |
| 5 | |
| 6 | #include <linux/skbuff.h> |
| 7 | #include <linux/module.h> |
| 8 | #include <net/xfrm.h> |
| 9 | #include <net/ip.h> |
| 10 | #include <net/protocol.h> |
| 11 | |
| 12 | static int ipip_output(struct xfrm_state *x, struct sk_buff *skb) |
| 13 | { |
| 14 | struct iphdr *iph; |
| 15 | |
| 16 | iph = skb->nh.iph; |
| 17 | iph->tot_len = htons(skb->len); |
| 18 | ip_send_check(iph); |
| 19 | |
| 20 | return 0; |
| 21 | } |
| 22 | |
| 23 | static int ipip_xfrm_rcv(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) |
| 24 | { |
| 25 | return 0; |
| 26 | } |
| 27 | |
| 28 | static struct xfrm_tunnel *ipip_handler; |
| 29 | static DECLARE_MUTEX(xfrm4_tunnel_sem); |
| 30 | |
| 31 | int xfrm4_tunnel_register(struct xfrm_tunnel *handler) |
| 32 | { |
| 33 | int ret; |
| 34 | |
| 35 | down(&xfrm4_tunnel_sem); |
| 36 | ret = 0; |
| 37 | if (ipip_handler != NULL) |
| 38 | ret = -EINVAL; |
| 39 | if (!ret) |
| 40 | ipip_handler = handler; |
| 41 | up(&xfrm4_tunnel_sem); |
| 42 | |
| 43 | return ret; |
| 44 | } |
| 45 | |
| 46 | EXPORT_SYMBOL(xfrm4_tunnel_register); |
| 47 | |
| 48 | int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler) |
| 49 | { |
| 50 | int ret; |
| 51 | |
| 52 | down(&xfrm4_tunnel_sem); |
| 53 | ret = 0; |
| 54 | if (ipip_handler != handler) |
| 55 | ret = -EINVAL; |
| 56 | if (!ret) |
| 57 | ipip_handler = NULL; |
| 58 | up(&xfrm4_tunnel_sem); |
| 59 | |
| 60 | synchronize_net(); |
| 61 | |
| 62 | return ret; |
| 63 | } |
| 64 | |
| 65 | EXPORT_SYMBOL(xfrm4_tunnel_deregister); |
| 66 | |
| 67 | static int ipip_rcv(struct sk_buff *skb) |
| 68 | { |
| 69 | struct xfrm_tunnel *handler = ipip_handler; |
| 70 | |
| 71 | /* Tunnel devices take precedence. */ |
| 72 | if (handler && handler->handler(skb) == 0) |
| 73 | return 0; |
| 74 | |
| 75 | return xfrm4_rcv(skb); |
| 76 | } |
| 77 | |
| 78 | static void ipip_err(struct sk_buff *skb, u32 info) |
| 79 | { |
| 80 | struct xfrm_tunnel *handler = ipip_handler; |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 81 | |
| 82 | if (handler) |
Patrick McHardy | 0303770 | 2005-07-19 14:03:34 -0700 | [diff] [blame] | 83 | handler->err_handler(skb, info); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 84 | } |
| 85 | |
Herbert Xu | 72cb696 | 2005-06-20 13:18:08 -0700 | [diff] [blame] | 86 | static int ipip_init_state(struct xfrm_state *x) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 87 | { |
| 88 | if (!x->props.mode) |
| 89 | return -EINVAL; |
| 90 | |
| 91 | if (x->encap) |
| 92 | return -EINVAL; |
| 93 | |
| 94 | x->props.header_len = sizeof(struct iphdr); |
| 95 | |
| 96 | return 0; |
| 97 | } |
| 98 | |
| 99 | static void ipip_destroy(struct xfrm_state *x) |
| 100 | { |
| 101 | } |
| 102 | |
| 103 | static struct xfrm_type ipip_type = { |
| 104 | .description = "IPIP", |
| 105 | .owner = THIS_MODULE, |
| 106 | .proto = IPPROTO_IPIP, |
| 107 | .init_state = ipip_init_state, |
| 108 | .destructor = ipip_destroy, |
| 109 | .input = ipip_xfrm_rcv, |
| 110 | .output = ipip_output |
| 111 | }; |
| 112 | |
| 113 | static struct net_protocol ipip_protocol = { |
| 114 | .handler = ipip_rcv, |
| 115 | .err_handler = ipip_err, |
| 116 | .no_policy = 1, |
| 117 | }; |
| 118 | |
| 119 | static int __init ipip_init(void) |
| 120 | { |
| 121 | if (xfrm_register_type(&ipip_type, AF_INET) < 0) { |
| 122 | printk(KERN_INFO "ipip init: can't add xfrm type\n"); |
| 123 | return -EAGAIN; |
| 124 | } |
| 125 | if (inet_add_protocol(&ipip_protocol, IPPROTO_IPIP) < 0) { |
| 126 | printk(KERN_INFO "ipip init: can't add protocol\n"); |
| 127 | xfrm_unregister_type(&ipip_type, AF_INET); |
| 128 | return -EAGAIN; |
| 129 | } |
| 130 | return 0; |
| 131 | } |
| 132 | |
| 133 | static void __exit ipip_fini(void) |
| 134 | { |
| 135 | if (inet_del_protocol(&ipip_protocol, IPPROTO_IPIP) < 0) |
| 136 | printk(KERN_INFO "ipip close: can't remove protocol\n"); |
| 137 | if (xfrm_unregister_type(&ipip_type, AF_INET) < 0) |
| 138 | printk(KERN_INFO "ipip close: can't remove xfrm type\n"); |
| 139 | } |
| 140 | |
| 141 | module_init(ipip_init); |
| 142 | module_exit(ipip_fini); |
| 143 | MODULE_LICENSE("GPL"); |